The invention relates to conveyors in general, and more particularly to improvements in chain or link conveyors. Still more particularly, the invention relates to improvements in conveyors which can be utilized to transport discrete sheets or groups of two or more (folded or unfolded) sheets between stations which are or can be remote from each other. Conveyors of such type can be used in newspaper assembling and printing plants to transport newspaper sections from a printing or folding station to a gathering, inserting, mailing or storing station, from a storing station to a gathering, inserting or mailing station or between other stations. The conveyors are driven in synchronism with parts which serve to deliver objects at a printing, folding, storing or other station and with parts which serve to accept objects at a storing, inserting, gathering or other station. Since it is not always possible to advance the objects along a straight path, such conyeyors must often be designed in a manner to ensure that they can be advanced along helical, looped, arcuate or other more complex paths as well as that the objects can change their orientation during travel between two spaced-apart delivering and receiving stations. Moreover, the conveyors must be sufficiently sturdy to ensure that they can support a large number of objects, for example, if the delivering station is remote from the receiving station so that the path portion between such stations must accommodate a large number of objects.
A conveyor which is designed to transport sheets of paper or the like is disclosed, for example, in published PCT patent application No. WO 86/03476. The means for guiding the links of the chain includes a rail having a U-shaped cross-sectional outline. Such rails cannot be readily bent to define arcuate paths. It is even more difficult to twist a rail having a U-shaped cross-sectional outline. On the other hand, it is often necessary to advance sheets along a complex path having one or more arcuate portions and/or one or more helical portions. Bending of a rail having a U-shaped cross-sectional outline involves much time and must be carried out by resorting to complex machines, especially if it is desired to prevent changes of the profile as a result of bending or twisting.